Mutagens
In genetics, a mutagen is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer, such mutagens are therefore carcinogens, although not all necessarily are. All mutagens have characteristic mutational signatures with some chemicals becoming mutagenic through cellular processes.
The process of DNA becoming modified is called mutagenesis. Not all mutations are caused by mutagens: so-called "spontaneous mutations" occur due to spontaneous hydrolysis, errors in DNA replication, repair and recombination.
The first mutagens to be identified were carcinogens, substances that were shown to be linked to cancer. Tumors were described more than 2,000 years before the discovery of chromosomes and DNA; in 500 B.C., the Greek physician Hippocrates named tumors resembling a crab karkinos (from which the word "cancer" is derived via Latin), meaning crab. In 1567, Swiss physician Paracelsus suggested that an unidentified substance in mined ore (identified as radon gas in modern times) caused a wasting disease in miners, and in England, in 1761, John Hill made the first direct ___ _________ _________ _________ ____ __________ ______ ________ _________ ____ _______ _________.
______ _______ ________ _________ _______ __________ _________ ___.
_________ ____ ______ _________ _____.
___ ______ _________ __________ ______ _______ _________ ___ ________ ________ _______.
___ _________ ______ ______ ________.
_____ ____ __________ __________ ___ ___ _________ __________ ________ ___ __________.
______ ______ ___ ___ _________ ______ ______ ________.
_____ __________ ______ _______ ______ ________.
___ ________ _____ ________ ______ _______ ________ ______ ______ ______ _______ ____.
________ ___ _____ ________ ____ _________ ____ _____ ____.
_________ ______ ______ __________ ___ ________.
_________ ___ _________ ______ ___ _______.
______ _______ _____ ___ _____ ________ __________ _______ ___ ___.
___ __________ ________ _________ _________ __________ __________ ____ __________.
____ ____ ______ _____ ______ _______ __________ ______ ______ _________ ___ _________.
_____ ______ ___ ____ ________ ____ __________ ___ __________ ___ __________.
_________ _____ __________ _________ _________ __________ ________ __________ ___.
________ ____ _________ ___ _____ ____ ______.
_________ _______ ___ ____ __________ ______ _______.
___ _________ __________ _______ _______ ______ _____ _______.
______ ____ ______ ______ ________ _________ _________.
________ _______ _________ _____ __________ ______ _____.
______ _____ _______ __________ ___ __________ ___.
____ __________ _____ ______ ________ ___ __________ _______.
___ __________ _______ _______ __________.
______ _____ _____ ________ ___ ______ ______ ______ ________.
______ _____ _____ ___ ____ __________ ____ ___ _____.
___ __________ _______ __________ _______ __________ ________.
______ _______ _____ ___ ____ ______ _________ ___ _______ ______ _______.
________ ______ _____ _______ _______ ________ ______ _____ _______.
___ _______ ______ ___ ___.
________ __________ ______ ____ ________ _________.
_____ ___ _________ __________ _______.
_________ ___ ______ ________ ____ ___ __________ ____ _______ ______.
_________ ____ _________ __________ ________ ___ _______.
________ ___ _______ ___ _________ _________ _______ _____ _________.
___ __________ __________ _________ ________ ______ ___.
__________ ______ _______ ___ _________ _____ ____.
___ ________ _________ ________ ________ _______ ____ ___.
______ _____ __________ _________ ______ __________ _____ _________ _____ __________ __________.
____ _________ _______ ______ _______ _________ ________ ______ _________ ____.
_______ _____ ____ _________ ____ _______ ________ ____ _____ ___ ________ ____.
____ ________ ___ ___ _________ _______ __________ _________ _____ _____ _______ _____.
________ ________ ___ ________ ____ _____ ______ ________ ___ ___.
_______ __________ _________ ____ ____ _______ ________ ______ __________ ____.
________ ______ ____ ______ ___ ___ _______ ______.
__________ _________ __________ _______ ____ _________ _________.
__________ _______ ________ _________ ______ ___ ___ ________.
____ _____ _______ __________ _________ _____ _______ ______.
______ ____ _______ _________ _________ ________ _____ _____.
_______ _________ _________ ____ ___ _______ _____.
_____ ______ _________ _________ ________ __________ __________ _________.
___ ____ ________ ____ _________ _______ _____.
_______ ___ ________ _____ __________ _________ __________ _________ _________ __________ ________ _____.
______ __________ ____ ________ _______ _____ ____.
________ _______ __________ ________ __________ ________ _____.
_______ _____ ___ ___ ________ _______ __________ ___ ________ ___ ___.
__________ _______ _______ ____ _____ ___ ______ _____ ______ _____ __________.
____ _____ ____ ______ ___ _____.
_____ _________ _______ ___ __________ ______ ___ ______ _______.
______ ____ _______ ___ _____ __________ ________ __________ _______.
_________ ___ _____ ________ __________ _____ _______.
___ _________ _____ ____ ____ _____ _______ _________.
_______ _________ ______ _________ _______ ________ ______ _________ _________ ___ ____.
__________ ___ ________ ______ _________ ________.
_______ _______ _________ __________ ________ _____ ____ _____ _______ __________ ____ _____.
_______ _______ ____ ________ __________.
_______ ___ ______ _________ _________ _____.
_______ _______ ______ ______ ___ ________.
____ _____ _____ _______ ___ ___ ____ __________ _______ _______ __________.
____ _______ __________ _____ _________ _____ _____ _________ __________ ___.
_________ ________ __________ _________ ________.
______ _____ _____ _________ _____ ____ ___ ___ _______ ____ _____.
________ ___ ____ ___ ______ ____ ______.
________ _______ ____ ___ ______ ___ _________.
__________ ___ ________ ______ _______ __________ ______ _____ ___.
___ _______ ___ _______ ___ _________ _________ _________ ______.
___ ________ _____ ______ _____.
______ _______ __________ ___ ______ _____ ________ ____ ________ _____.
_______ ____ _________ ________ ___ _____ _______ __________ _______ _____.
_____ ____ _________ ___ __________ ________.
________ _________ _______ ___ ________ ___ ________ _____ _________ ______ _________ ___.
______ ______ _______ ______ ________ _________ ________ ____ _______ _____ _______.
___ ____ _____ ______ ___ ___ ___ ___ ____ _____ _______.
_____ ______ ________ _______ _____ _____ ______ _______.
___ ____ _____ _____ _________ ______ _________ ____ __________ _______ _________ __________.
________ _______ ___.
Get Full Answer on WhatsApp